SEATTLE -- Guns and explosives were found in the apartment of a man accused of killing Seattle police Officer Tim Brenton, Assistant Seattle Police Chief Jim Pugel said.

At a Saturday news conference, Pugel described 41-year-old Christopher John Monfort as a "domestic terrorist" who appeared to have acted alone in the officer's fatal shooting Halloween night but is also a suspect in the Oct. 22 firebombing of four Seattle police vehicles at a city maintenance yard.

Police said there is a similar key piece of evidence linking the two crimes but will not say what that evidence is. The Seattle PI reported that American flags were left at both scenes.

Articles printed about the bombing were found in Monfort's apartment along with makeshift explosive devices, an assault rifle, political science books and another gun, Pugel said.

Police said Monfort had attended community college and studied criminal justice at the University Washington.

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The explosive material found at Monfort's apartment will be analyzed to determine if it matches that which was used in the police vehicle arsons, Pugel said.

Pugel said the two officers who were fired upon Halloween night appeared to have been chosen randomly.

A profile released by SPD before a suspect was identified said the shooter had some sort of grievance that was bothering him and he may admire or act like a police officer. Read entire profile

KIRO 7 confirmed through multiple sources that Monfort applied at the Seattle Police Department but was rejected.

Books found in his apartment indicated that he may have been a student at the University of Washington at one time.

Monfort was shot Friday when Seattle Police detectives pursued a tip at the Terrace apartments in Tukwila on Friday, Tukwila police spokesman Mike Murphy said.

Pugel said three SPD homicide detectives approached Monfort outside the apartment building and had a quick exchange of words with him before Monfort pulled a gun, fired, then ran from officers.

When Monfort stopped and turned toward officers with his gun drawn, three officers fired four to six shots.

Pugel said Monfort's gun misfired when he attempted to shoot at police.

Monfort was taken to Harborview in critical condition with gunshots to the head and side. He was upgraded to serious condition Saturday following surgery, Harborview Medical Center spokeswoman Susan Gregg-Hanson said.

Pugel said police came to the apartments after receiving a tip from a citizen who noticed that the type of car police were looking for had been covered up with a tarp soon after the shooting occurred.

That vehicle was found in the apartment parking lot Friday.

Neighbors in the apartments said Monfort kept to himself.

Pugel said as the investigation continues, anyone who knows Monfort or has details on the case is asked to call the Seattle Police Department or Crime Stoppers at 1-800-222-TIPS.

The Seattle Police did not want the public to see the Saturday briefing live on television or online. Four TV news organizations, including KIRO TV, had joined together to use their resources to bring the briefing live for the public, but the SPD prevented that from happening. Watch the news conference here.